Increase Image DPI Online
DPI is a number stored in your image file that tells a printer how large to print each pixel — it is metadata, not picture detail. This tool writes a new DPI value (150, 300, or 600) into that field and hands the file straight back, which is exactly what you need when a passport office, print shop, or upload form rejects a photo for being "under 300 DPI." What it does not do is add detail that was never captured: a 400 × 400 photo tagged at 300 DPI is still 400 × 400 pixels. If your file was rejected for pixel dimensions rather than DPI, changing this value will not fix it — the sections below explain how to tell the two apart.
Target DPI
300 DPI is standard for documents and passport photos. 600 DPI for high-quality print.
Drag & drop your file here
or click to browse
JPEG, PNG, TIFF · Max 20MB
How it works
Upload your image (JPEG, PNG, or TIFF).
Select your target DPI — 300 is standard for documents, 600 for high-quality print.
Download the new image with updated DPI metadata.
Why use this tool
Required for passport photos, visa applications, and print-ready files.
Needed when online submission portals require a specific DPI.
Instant — no need to open Photoshop or install any software.
If the result is not what you expected
The image looks exactly the same after changing the DPI
That is the expected result. DPI only changes how large the image prints on paper, not how it looks on screen. A 1200 × 1800 photo looks identical at 72 DPI and 300 DPI on a monitor — the difference is that at 300 DPI it prints at 4 × 6 inches, and at 72 DPI it prints at roughly 16.7 × 25 inches. Nothing about the pixels changes.
My photo was still rejected after setting it to 300 DPI
The rejection was almost certainly about pixel dimensions, not the DPI tag. Requirements are usually written as both: "35 × 45 mm at 300 DPI" really means 413 × 531 pixels. Check your file's actual pixel size — if it is smaller than what the form requires, you need a higher-resolution original photo, because no tool can invent detail that the camera never recorded. Use Resize Image Online if you have enough pixels and just need different dimensions.
I need a specific DPI that is not 150, 300, or 600
Those three cover almost every real requirement — 150 for draft printing, 300 for document and photo submission, 600 for high-detail print work. If a form asks for something unusual like 200 or 1200 DPI, setting 300 is usually accepted because the pixel dimensions are what actually get checked. Worth confirming against the specific form rather than assuming.
The DPI reverted after I opened the file in another app
Some apps strip or rewrite metadata when re-saving — messaging apps and social platforms are the worst offenders. Download the processed file and upload it directly to wherever it is going, without opening and re-saving it in between.
Frequently asked questions
- No. DPI is metadata — it tells printers how to scale the image on paper. Changing DPI does not add pixel information or change how the image looks on screen. It affects print size and whether portals accept the file.
- Most passport and visa applications require 300 DPI at the specified print dimensions.
- 300 DPI is the standard for most document and photo printing. 600 DPI is used for high-quality print work like fine art or detailed technical diagrams.
- No. Resolution is the pixel count (for example 1200 × 1800) and it is fixed when the photo is taken. DPI is a separate number describing print size. Raising DPI without changing pixels makes the image print smaller and sharper on paper; it never adds detail. Tools that claim to "increase resolution" are upscaling — guessing new pixels — which is a different operation entirely.
- Multiply the size in inches by the DPI. For a 35 × 45 mm photo at 300 DPI: 35 mm is 1.378 inches, so 1.378 × 300 = 413 pixels wide; 45 mm is 1.772 inches, so 1.772 × 300 = 531 pixels tall. That is where the common "413 × 531" passport photo figure comes from.